Comprehensive code documentation

Properly document code with clear, accurate, and useful comments using the correct syntax based on context:

1. Use /// to document items (structs, functions, etc.) that follow the comment:

   /// Struct to store runtime state of the compute monitor thread.
   /// Handles tracking Postgres availability and managing downtime metrics.
   pub struct ComputeMonitor {
    // ...
   }
   

2. Use //! for module or crate-level documentation that applies to the enclosing item.

3. Document all public structures, traits, and functions with explanations of:
   • Their purpose
   • Usage considerations
   • Potential pitfalls or caveats
4. For complex data structures, include explanations of fields and their relationships:

   /// Range of LSNs for page requests
   /// - request_lsn: LSN specifically requested by compute
   /// - effective_lsn: LSN actually used for the request (may differ from request_lsn)
   /// Note: Primary computes typically use request_lsn == MAX
   pub struct LsnRange {
    pub request_lsn: Lsn,
    pub effective_lsn: Lsn,
   }
   

5. Ensure comments are accurate and up-to-date. Never merge incorrect comments with the intention to fix them later.

6. When referencing other code elements, use proper linking syntax: [Type::method()] to enable IDE navigation.

7. Avoid redundant comments that merely restate what is already clear from the code or function names.

Good documentation serves as both a reference for users of your code and as context for future developers (including yourself) who will need to maintain it.